Paint Bucket tool introduction
Use the Paint Bucket tool to assign materials and colors to entities in your model. You can use it to paint individual entities, fill a number of connected faces, or replace a material with another throughout your model. Activate the Paint Bucket tool from the Principal Toolbar (Microsoft Windows), the Tool Palette(Mac OS X), or by choosing Paint Bucket from the Tools menu.
The Paint Bucket tool is separate from the Apple Color Picker used to select colors and materials (Mac OS X).
Keyboard Shortcut: B